 FOB Chapman was built around the original Soviet airfield servicing Khost while FOB Salerno was built slightly north of this facility, together these two bases were the vanguards of the city of Khost since they were only several miles from the city, often sending forces to respond to attacks in the provincial capital.The Battle of Tora Bora took place approximately 30 miles north of Khost.Because of this geographic isolation FOB Salerno, being isolated from the rest of Afghanistan on one side and having the Federally Administered Tribal Areas of Pakistan on the other, the area remained vulnerable to insurgent attacks, supplies often had to be airlifted into the base when the path to Gardez was impassible adding to shortage and cost issues.